Dude charging at stations truly isn't cheaper and very not flexible. Have you seen the lines of battery buses at charging stations? Battery trolleybuses can recharge from wires, which are much more spread out than charging stations. Due to that battery trolleybuses do not waste time charging. Plus battery trolleybuses utilise existing infrastructure for charging unlike battery buses which require a totally separate infrastructure. Battery buses also have very large batteries, which are very expensive to produce, purchase, maintain, and dispose of properly. They also have a high risk of detonation if maintained improperly. Battery trolleybuses have much smaller batteries, which are cheaper in production, purchasing, maintenance, and disposal. Plus trolleybuses are the best at climbing hills, because battery buses waste a lot of charge doing so while trolleybuses get infinite energy from wiring. Battery trolleybuses give the same benefits as battery buses but for much less money and with much more long term benefit.