As is their right I suppose. Everyone should know by this point that saying things on Twitter can get you fired, so you should make that reality part of the risk/reward calculation when considering whether it's worth posting anything. Was this tweet worth it? Probably not worth the hassle at any rate, though there may be some value in learning you work for a company that would do this.
Social media only exists for the benefit of high-follower count individuals or large corporations.
Become unlucky enough and your large corporation finds you negatively tweeting about a high-follower count individual? Straight to HR.