Down by the river, afternoons are spent feasting on all manner of Isaan fare served to you as you sit on mats under the trees. If it gets too hot, take a swim or float down the river on a rubber tire.
Although not many of the vendors speak English, with a bit of pointing and a lot of smiling you'll survive and undoubtedly get to taste a few new flavours. Remember in wet season the rapids are underwater and so many of the vendors are not around then.
A large selection of interesting Thaisnacks, including frog skins and fish innards, are also sold at many stalls near the rapids.
Away from the river, there's a handful of rice and noodle shops scattered across town and, in the evening, a reasonably sized night market sets up near the main intersection on the road to Ubon Ratchathani.