"How to [...]?" and "Where to [...]?" Questions that are not questions. Is this defensible?

Adding a question mark to the end of a "How to" or "Where to" sentence appears to be quite common. Here are two examples from this very site:

How to punctuate a list of questions? (link)

Where to put the periods when using a parenthetical sentence? (link)

In my mind, the question mark doesn't belong at all, and it bothers me.

Am I being unreasonable? Is this practice defensible?

I'll give a shot at answering my own question.

The obvious correct alternatives are not entirely satisfying.

How does one punctuate a list of questions?

This comes across as too formal for many people.

How do I punctuate a list of questions?

This is too personal, perhaps selfish sounding.

How do you punctuate a list of questions?

This sounds like it's asking for opinions rather than established usage. (On this site you'd get a warning about a subjective question.)

How to Punctuate a List of Questions

This sounds like an introduction to a guide.

So the problem is probably that using one has become too formal and nothing has reliably taken its place.

Perhaps a better alternative would be to rephrase the question:

How should a list of questions be punctuated?

The question mark, by itself, is enough to make any statement a question. For example:

The sky is blue?

By mere word-choice, the sentence appears to be a simple statement about the color of the sky. However, the question mark adds clear disbelief and uncertainty on the part of the speaker, and the sentence above can be read with an implied introductory phrase:

(Is it true that) the sky is blue?

While I personally wouldn't use either of the examples you provided, their uses seem like attempts to depersonalize and shorten the questions being asked. Consider:

• How to punctuate a list of questions?
• How (should I) punctuate a list of questions?
• (What is the right way) to punctuate a list of questions?

Note that the expanded variants are both several words longer, and introduce unnecessary conditions to the basic question. (Specifically, the second implies a question of style rather than correctness, and the third prespposes the existance of the wrong way to accomplish the task.)

The sentences would be properly phrased in prose as follows:

How do I punctuate a list of questions?
Where do I put the periods when using a parenthetical sentence?

[D]o i can be alternatively phrased as does one, if formality or third-person point of view is required.

The examples you gave would be more suited to the title of a how-to guide, such as:

How to Punctuate a List of Questions

In other words, the article that follows would instruct one on punctuating a list of questions. This form is not for a question, but instead for a title, and thus should not be punctuated at all.

I have always thought of how to do x? as short for something like how [is one] to do x?, where the question mark is necessary.

Is this practice defensible?

Obviously, since people have defended it. ;)

Perhaps the real question is down to whether the defense is justified.

For my part, I'll search a post for '?' and if the first hit is ..

Know someone who can answer?

(N.B. Directly quoted from StackOverflow, which itself seems to fall into the same 'not a sentence' area.)

.. I will scan the post for a goal then directly, put 'How to' in front of it, and a '?' at the end. I deliberately choose not to alter the goal in any other way, in some sense as a way to indicate:

Look how easy it can be to turn a goal into a question!

OK - not for the 'grammar conscious', but then, there are not too many of them who make comment in any group other than this one.

English is an evolving language. This is a very good example for change. If "How to [goal]?" is not a valid question then it is English that should change.

Am I being unreasonable?

IMO (for whatever little it is worth) yes.