Not necessarily. If you're trying to attract high-tech companies to an area that has no tech workers, then it makes sense to give the *first* company an incentive to build there (with smaller and smaller incentives as more companies come in). If there aren't any tech workers already in the area, it's going to cost a big company a lot of money to bring them in. That's a very real, tangible cost to the company.
Once the area is established and has a good number of tech companies and workers, the tech workers (who tend to make good money) will settle in because they can always find a new job at another company nearby. Then they'll spend their larger-than-average salaries on eating out, going to the movies, and all those other things that bring in sales tax dollars and put money into the pockets of "regular Joe" types.
To give you an example of this, consider the neighboring Colorado towns of Boulder and Longmont. Back in the early '60s, Longmont was largely an agriculturally-focused town and Boulder was, well, Boulder. In the '60s, IBM built a large plant smack dab between Boulder and Longmont and it employed thousands (my parents met while both were working for IBM, incidentally).
Before long, other tech companies (like Maxtor, Seagate, WD, StorageTek, National Semiconductor, DigitalGlobe, Amgen, Intrado, Xilinx, AMD, Webroot and more) opened up new offices and plants (or started in) in the Boulder/Longmont area. Housing prices started growing faster than the national average. Longmont's population exploded from about 23k to about 71k; Boulder's population increased by half, from about 66k to about 94k.
By the tech boom of the late-'90s and early-'00s, the Boulder/Longmont area had more tech workers per capita than Silicon Valley and housing prices were well above those of the surrounding areas. Even after the tech bubble burst, there was still plenty of new activity. The Boulder/Longmont area has seen amazing economic growth, and a much of that can be traced back, directly or indirectly, to IBM opening up its plant and employing thousands of tech workers where there were none before.
Now, in the case of this Apple datacenter, with only 100 employees, it's hard to see if that will make a large enough impact to help the local economy in the way that IBM's plant helped that of Boulder and Longmont, but sometimes you just need to take that first step to bring that company that everyone's heard of to your area; then maybe others will follow.
And *that's* why it sometimes makes sense to give businesses tax breaks.
