At the end of the day it all comes down to whats in the cup.
At our airport store we use triple baskets for 2 reasons.
1) Being that it is all takeaways, and that some time ago industry standards for takeaway cups were decided to be 8 oz and 12 oz instead of 6oz and 12 oz. The triple baskets allow us to pull full 30-35ml espressos in a 8 oz with the same flavour profile as we get in our 20-25ml espressos in a 6 oz cup at the roastery. This means that the extra coffee essentially gives us the chance to pull 1.5 restricted espressos into a 8oz cup keeping the espresso to milk ratio ideal, for us. You are talking about an extra 3.5 grams of coffee per espresso which is hardly noticable $$$s wise.
2) Being that it is a remote location with 6 baristas covering 120-130 barista hours a week, the extra coffee gives a bit of room for error. The baristas can pull a technically poor espresso but still get a great shot. This is important where we have experience varying from 15+ years to 15 weeks behind the machine.