Pumped Breast milk or Formula while not at home

Hello All,

I am planning to get a breast pump for feeding the baby when we are outside our home. For ex, going to pead or friends place. I want to feed my baby with breast milk as much as possible but, Since pumping breast milk is a lot of work(at least a bit), I am wondering if formula milk can be fed as a replacement for those outings. Has anybody experimented with this and found formula feeding easier/quicker than breast milk? If so, I might just skip getting the breast pump. Kindly post your suggestions.

Thanks in advance,
Lavanya.