My insurance company tells me that when a trailer is attached it's covered under liability, no different than a cargo box on a hitch. Rated capacity never factored into the discussion, just don't overload the OEM hitch that I have installed.

But now we're talking about differences in people's specific insurance coverage, which may vary by country, state, province, provider, and legislation and not the overall point which is that owning a daily driver pick up truck just because you occasionally tow is more an excuse than a nessecity for many , many truck owners.