Welded seams are great for RIBs as they are cheap and easy to do. They are also easy to replicate on repetitive seams. RIBs are also inflated about 90% of the time.
Takacat boats are typically folded and unfolded hundreds of times in their lifetime. Welded seams will become brittle and start to leak. Welded seams are also not 100% repairable, they can only be patched over.
Glued seams are more flexible over time and can have higher holding power in complex shapes. Our house blend glue is specifically engineered to maintain its flexibility over many years and after extend exposure to UV.