As someone suggested, why not just collect whole cans in the breakroom, especially if you’re in a state with a bottle/can deposit?
Or even put out a can for loose change?
Because there is a non-zero number of people who will donate the tab but want the 5 or 10 cent deposit for themselves. Plus the cans take up more room - people at my job were collecting cans for the deposit and were made to stop because there were just too many bags of cans sitting around before they were taken out of the building. Sure, they could have taken the bags out more often - but they didn’t and that would have just moved them to someone’s car or garage anyway.
Because collecting cans is so bulky. Pull tabs are nice and compact.
That sounds a lot like “I do it because it’s easy and convenient, not because it is cost effective”.
Definitely. 
Ref upthread
And now some facts, from here: https://manvillerecycling.com/recycling-aluminum-cans-vs-pop-tabs/
It takes about a thousand pull tabs to make a pound of aluminum, which nets you a whopping $1.18, whereas you can get the same amount of aluminum with about 34 empty cans. BTW, it seems that the pull tab is made from the same aluminum as the can itself, so no special value there.
The thing to remember here is that 1000 pull tabs = $1.18.
I’m trying to think of what common disposable object would be more effective to collect. Surely there’s something else in a typical office that would yield more money?
There certainly is, and it can be found in a lot of people’s pockets, in couch cushions and car cup holders.
I think that is in Canadian dollars. How much is that in real dollars? Still sounds like a lot more than what I can get around here where I’m at this week which is about 25 to 30 cents per pound.
I thought the value in the pull tab is that it’s not coated in epoxy resin and paint/ink, so it’s easier and thus cheaper to recycle. Even the lid of the can still needs that epoxy coating on the inside to prevent the acidic soda from eating away at the aluminum.
Find a recycler that separates them from the cans for that reason, or uses a different process at all when it comes to cans vs. tabs.
Pennies. People tend to treat them as disposable now.
Even collecting pennies would net more.
When this foolish BS about collecting pull tabs all started, the pull tabs were like this:
And just as coated on the interior surface as the rest of the can.
FYI, that image is borrowed from this very interesting site on beer can design history. Which can pretty well be generalized to cans for beverages of all natures:
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