Do cream Dispensers/Chargers produce more cream than Cream Bottles purchased in Stores?

My question is that, Do they make more cream than if i was to buy a bottle of Whipped cream from the stores? In that case would I be getting more value for money buying a Cream dispenser/Charger or should I stick to buying whipped cream bottles? I plan to run a milkshake Stand and having to buy whipped cream bottles ie.20+ sounds expensive in the long run so keen on your thoughts and opinions.

Cheers