One reason is that Chinese people are less lovable/"adorable", at least in terms of appearance. At first glance, many Chinese kids/young girls are not "adorable" (not pretty). It is rare to find a Chinese young kid/girl who is pretty. But it is rare to find a western one who is not pretty -- they make you feel you want to love them. Often, the parents look awful (old, fat, etc.), but their young kids really look "adorable", like angels.

So I think the Chinese people feel "love'/"be loved" less frequent than Wetern people. -- and this is the main reason we use the word "love" less frequently.