Perhaps, but do you really want to bet your freedom on the whims of some IRS agent?  The penalty for underreporting income is steep, especially when you're talking about tens of thousands of dollars (as many Steemsters are). And there's no statute of limitations for underreporting income.  

Furthermore, unlike sales of Facebook or Reddit accounts, the Steem blockchain is a public record and lasts forever.  It's as easy for the IRS to to read the chain and see who made what and when as it is for you or me to do so.  

The IRS is already  cracking down on unreported crypto income.   Witness its sweeping subpoena issued to Coinbase.com.  Cracking down on Steem would be so much easier for them--no subpoena required.