Tom,
In my book there is no such thing as a dumb question.
Just dumb answer. Hopefully this isn't a dumb answer.

This is just the way I see it.

One hull weighs between 20 and 25kg.
It is supported by 4 bolts.

If the load was even between front and back it would be between 5 to 6.25kg per bolt.

I would expect each bolt would be capable of taking over 100 times that weight.

Compare this to the tension load applied to the hulls at the rear beam when fully powered up upwind and double trapped. This load can be so high that I know of boats that have snapped inner rear beam bolts that were 8mm in dia. If really concerned look up the tensile breaking strain of an 8mm bolt just to see the type of loads involved when sailing and then compare it to trailering.
I personally don't see a problem with trailering by the beams.
Regards,
Phill