Yeah, this is a fold with out a thought, if you were drawing to the the nuts it would depend on how deep the stacks were (include these as the decision can change, if they are a SS you stand to gain very little from hitting, if they are a big stack it might be worth chasing (unless it's an SNG/MTT where it would depend on how much of your stack that would cost)).

It looks like he hit top pair and wanted to take it right there or bought it due to the weakness pf.