For anyone in the know, what are reddit's big costs? Wikipedia has employees @ 230 in 2017, for whatever context/scale that contributes. The article doesn't me

For anyone in the know, what are reddit's big costs? Wikipedia has employees @ 230 in 2017, for whatever context/scale that contributes. The article doesn't mention plans. Are they just getting while the going's good, or is there something expensive that they plan on doing?