Bullshit.
Just because you've had some lucky grows, and thus far not had to worry about ph doesn't invalidate it as among the most crucial measurements to your plants health.
An improperly balanced ph will inhibit the absorption of nutrients and minerals, can cause stunted growth, and can cause the death of smaller plants and seedlings.
If you are lucky enough to have a medium that stays balanced and buffered at exactly the right ph level (unlikely, but possible) and be using a water source that is also stable at the same ph level (extremely unlikely unless you are using rainwater) then checking ph levels will make no difference.
For the other 99.9% of us, ignoring ph is just stupid. Yes, you will probably still get bud from your plants, but, at best, you will be trading maximal results for a slightly easier grow. And, in many cases, you'll just stand around scratching your head, wondering why all your plants are "mysteriously" dying around you.