First off, trying to use their inclusion of Bootstrap as a negative comes off as elitist nonsense. Second, the file you are discussing is actually 131KB uncompressed and 43KB when gzipped. No issues there.
This sounds to me like a serious case of "I hate this because someone else is making money off of it instead of me".
Anyway, including Bootstrap to use two containers with different background colours is a lack of professionalism. Why can't you make it yourself? I'd argue that it would take an experienced web developer approximately the same time to do it without Bootstrap.
I don't really hate it because he's making money off of it, it's just that it feels like a ripoff to me. For $99/month [1] you can get a new website, specifically designed for you by a web developer, every month.
[1] it looks like he has realised $99/month is a joke.