I think it would just require a bit too much effort for someone with no previous experience to make a website from scratch just for a Feralheart group----and oftentimes one that will go inactive within a few days or weeks and make the site (plus all the effort that went into it) useless. Site creators are just much easier and quicker to use for someone who wants to start up a roleplay right away. Some people aren't as focused on websites as well, and maybe just use it as a 'dumping ground' of information and not much else. Plus, coding can be difficult to learn for some people, and others just don't have the patience. For some people yes it might take a week to learn, but for others it could take much longer.
I haven't run across many people who have made their own group websites from scratch, but I think it depends on if you want to put in that much effort or not. Making a website that way CAN be fun and rewarding, but it's just not the right option for most. Both making a website from scratch and just building one with a website maker have their positives and negatives but both serve the same purpose. So really I don't see the need to judge either one, it just depends on what the group leader is more comfortable with, how much time and effort they are willing to put forth, and what option would be best for them.