Yes, I have actually. Transitions are just covers for the required gap at ends. You will need one if you change direction of installation from room to room, run up against another type of floor, or just doing single room. The most issues stem from incorrect installation due to lacking expansion gaps, poor assembly by not locking planks correctly or nailing/caulking down sections of the floating floor. If you install the underlayment correctly and follow all guidelines for end gaps, including at doorways, dont nail or caulk any portions of floor down, you can run a whole house without a single transition without any issues. Also, different manufactures have different recommendation and I would not use a product that said you had to use transitions between all rooms, and have yet to see one that specifically requires this.

Your friends floor is likely an issue with no end gap allowances for expansion. Some contractors will install floor without pulling up baseboards to cut their costs and try to cover end gaps with shoe molding. Most floors require at least 3/8 expansion gap against any hard surface.