Although inflatables are large and heavy, they cover a large surface area and will have a minimal impact on your grass. It will flatten grass temporarily, but we've never heard of any permanent damage. We will put stakes into the grass to hold the inflatable in place, but these holes are no larger than what you typically see with lawn aeration.
Once or twice a year, we do accidentally hit sprinkler lines with our stakes. If you're worried about us hitting your sprinkler lines or other underground utilities, have them located prior to our arrival by contacting Colorado 811 at https://www.colorado811.org/. We are not responsible for damage to unlocated utilities, including sprinkler lines.