At launch they allowed full XP progression through portal maps for players, even playing against only bots. People figured out you could multiply that XP though server settings, and EA removed all XP gain from portal in response instead of just fixing the multiplier.
I have seen them allowing full XP on "select experiences" recently but since there is no good server browser, I can't say if there are bot matches opening up again with XP gain.
I'm somewhat there with you. I don't really want to play bots myself, though I abuse casual for the XP grind during XP weekends. But if people want to just play bots... in the game they paid $70 for... who cares? EA made a pretty silly decision on this one.