A1- if they made an exemption for pick up only items it would be easy for sellers to list pick up only, and then say in TOS that they will be happy to post.  End of buyer protection.

A2- when I am looking for something and am not exactly sure, I save everything that could possibly be useful, then go through them and either buy one of them (and delete rest), or if still unsure I may continue my search some other day.

For instance, I was making dress for little fairy, so I was looking at all sort of laces, trims, beads and sparkles, and over time deciding which ones to use.

Or, if it is just a specific item, then I may compare prices&shipping costs, and if I am in hurry to get my item looking where the seller is.