Well .. they don’t get much from me anyway .. and I like having that lump sum once a year in order to purchase big $$ items.
Lots of people are the same way. If you keep $1000 more in your paycheck and keep it in the bank, you might end up with an extra $15 or so in interest over the course of a year (assuming a 3% savings interest rate and a linear addition to the account over the year). It’s not much, but you could look at it as two decent six-packs.
The IRS calculator will tell you what to do and will always give you the closest number of exemptions based on your numbers. It might suggest that you underpay slightly or overpay slightly. What you actually do is up to you. Sometimes it’s tough to calculate how much you’ll have in variable deductions (like charitable giving) ahead of time, but it is usually helpful (especially if you’re getting a large sum back every year).