Self-Inflating Sleep Mats
When camping, it really is necessary to use some form of sleeping mat. Not necessarily for comfort, although that is a bonus, but to protect against ground cold.
You could use an airbed, (Mostly too heavy for backpacking.) or a closed cell foam mat. (Excellent! but a little bulky even when rolled up.) The best all round solution is a self-inflating sleep mat.
The self-inflating sleeping mat gives the best of both worlds. Good insulation + a small packed size.