It is right tool for the job is best. One does NOT need a 1 ton to tote a smaller trailer. Nor will you get "JUST BY" with smaller trailers. 
I saw a Harley yesterday toting a trailer at 65-70 mph no less. They were not having an issue! yeah it probably weighed no more than 150 lbs.....but still, a 1ton or 3/4 was not needed for that weight. 
One would be surprised what style of rig probably literally moves a space shuttle, airplane at an airport etc. Most will use a larger chassis as they can handle more literal hours before needing repair vs lighter duty parts etc in lighter duty chassis. 
it is like asking, do I need an 8 lb sledge to pound in a brad? one will kill ones fingers before driving the brad in. Hence why one uses a 4 oz hammer! If I am pulling a 2000 lb trailer, I can stay with in weight limits, why not use a smaller pickup, car with a 4 banger! With 200 ponies in some of these rigs, one will not be under powered, chassis should handle it etc.
 
Marty 
Marty,   
I think and hope we are all having some fun with this forum thread.   Nobody said that you need a one ton to tow a motorcycle trailer or even a tent trailer.   As this is an RV forum and there are many different kinds of RV's it can be fun to discuss tow vehicles.   And so far it has been civil.      We are just having fun and the OP started this all, not me.