It's not slavery of course, but it is a troubling approach to marketing. If I'm going to a bar on my own account (rather than to participate in some prearranged party) then I don't want to be hustled by some total stranger into supporting something I've never heard of as a condition of entry.

I know I'm out of the mainstream on this, but as a European one of the most difficult things about living in the Us is the lack of regard for personal space. Before I knew the appropriate code words I went through a stage of fending off signature-gatherers with clipboard petitions by pretending not to speak English. If you asked me to vote for something on my smartphone as a condition of entry to a bar then my first response would be to find some other place to have a drink.