Ah bribery... Hmm, somewhat interesting how we as society have come to accept it in situation like these. I wonder if more research will lead to banning it and punishing people from even attempting. Then again people deciding on punishments are ones that benefit from the bribery so very likely not.
I think this and bribery are different, albeit subtly. Bringing in donuts, which have little material value, to ensure the audience is attuned to your presentation and not distracted by hunger is different than paying someone, for instance.
The fact it’s done openly and for all also legitimizes it.
I’d agree it could introduce a bias against those who don’t bring them.