\You must be a young un eh! Dual pipes were the norm on all twins cylinder engines at one time. Yamaha 100cc Twin had 2 pipes. Honda 150, 160 and 175s all had dual pipes. Dual pipes are best for freeing up that bulging power of the twin 250 lol.
Not sure what you consider "young"...but from an engineering perspective its a waste. Trying to sell a bike into a price point market with added mass for almost ZERO reason seems like a waste.
Goal: Small, LIGHTWEIGHT, economical, cheap bike to sell to the short distance commuter crowd and as an intro bike...
2 exhaust cans:
More weight - check
More cost - check
More power - nope
More efficiency - nope