>It has been the standard for quite a few years, and I cannot imagine only having 100A service in a proper house

100A service is fairly normal here for smaller homes. As heating here is primarily done by natural gas furnaces rather then electrical heating. Which make sense; gas is way cheaper to heat with here then electricity. And it saves a dollar for the developer.

I don't know about larger homes though; I'd imagine that they'd have 200A circuits but it wouldn't surprise me if they didn't unless the builder specifically requested it.