I still shop Bo Bae occasionally, though a lot of that action has moved to other areas. Nowadays, I shop more at the Indian and China Mega-Mall section of Chinatown. Mostly because I'm already in the area. A trip to Bo Bae is a specific mission when I want Songkran shirts in the off season. If you're just looking for cargo shorts, I wouldn't make a special trip anywhere. Just about every mall, BigC and Lotus has at least a few pop-up stores that sell things like that. Or MBK, or the malls around Chatuchak (which, unlike the weekend market, are open during the week- though I think they close on Mondays- someone may chime in with a correction.) Even some of the MRT underground shopping areas have pop-up clothing shops. No need to make a special trip. It is hit and miss, but low effort.