I asked nicely why do I need to give my phone number and I was told that to register me as a member so I can get the discount.
I declined and said I don’t want to join and would like to just pay.
I've just said "I don't have one" when asked this for awhile. This never seems the phase the cashiers, I'm guessing they know what that really means. Half the time I still get whatever discount, though I've never tried to sign up for a membership saying that.
If it's an online form my phone number is just (local area code)555–5555. I've never had that not take, except for one case where it automatically enabled 2-factor auth and I had to create a new account.
They don't. Well, TI does but not anywhere near the the node size of the three you mentioned: https://en.wikichip.org/wiki/technology_node