At least vary the distance A mat won’t teach you anything about differing turf conditions.

….If I could use a mat, I think I could drop 3-5 strokes a round. I don’t get enough practice with deep, lush rough.

It's not dangerous, but it does not give you any real indication of how well you will chip on grass. Listen to the contact. If you hear crisp ball contact, that's a plus. If you hear the club strike the mat first, you're in trouble.

Personally, as long as you're hitting ball first and accelerating through impact, you're developing good habits. The club will bounce on the mat, depending the type of surface, but nothing that is going to hurt your game. That's just MY opinion, I'm a pretty good wedge player. The difference is the feel/touch you can only acquire practicing near a chipping area/green.

I chip a lot off a mat in my backyard as well. I have a mat that has 2 different grass lengths and chip balls off both sides. I have noticed that my short game is better as a result of the consistency of my practice.

I don't think it will hurt much but as Don said, you won't get different conditions of feel but if you are just focusing on keep the short game in check, it's good.

Most definitely practise on grass. Mats provide do provide forgiveness, they are good for convenience at home however prioritise mostly practising on the grass and on different types of grass (long, short, tight lie, lofted lie) that way you know what shots to play when on the course.

I agree with the above poster. As long as you are hitting the ball first, no problems. The real issue is that mats don’t provide accurate feedback on miss hits behind the ball. You will get incredibly favorable results as compared to actual turf.

The only problem I see with a mat, is you get a perfect lie every time.I'm a muni player, and In my world, perfect lies are only a pipe dream....

Practice is Practice but perfect practice is better. Hey...at least you're swinging. Keep doing what you're happy with.

One of the things you can do is put a towel about a club head behind the ball and make sure you miss the towel. That will ensure you’re making clean contact. It’s a good practice even if you’re not using a mat. If you use the bounce properly, you can still chip effectively without making crisp contact, but you want it as crisp as possible.