Maxxis mudzilla 10" X 28" - 12" weigh 35.6Lbs each with 1.181" tread depth
Interco swamp lite 10" X 28" - 12" weigh 38.0Lbs each with 1.562" tread depth
So you are right they are a little lighter only 2.4Lbs difference in weight, but you gain that back with the tread depth .381" of extra tread.
Plus the rubber compound is super buoyant, Step-down tread pattern adds to the lug strength, and helps in reverse having more edges to grip terrain.
Everyone has there own opinion but for the extra 9.6Lbs total for all 4 tires it is worth getting the swamp lites. You will not be disappointed.
Need anymore tire spec's let me know I have a 3" binder of info on ATV tires.