The visibly drunk or social player at the table is playing for action, not to win. They will call you with anything if they like the interaction. Do not bluff them.

Why they do it

This player type is there for the experience. Winning and losing is secondary to being part of the game. Bluffing them doesn't work because they're not thinking about whether you have it - they're thinking about whether they want to play the hand.

The adjustment

Value bet everything. Bet any pair, bet draws with equity, bet top pair on the river even when the board is scary. They will call. Do not run a bluff - they'll call that too and you'll be confused.

What it's worth

One correct value bet on the river against a social player instead of checking back is worth $30-60 in pure added EV per occurrence. Over a session with one of these players at the table, that's $100+ in found money.