AT&T doesn't believe the iPhone X needs any aggressive promotion support, so it doesn't offer any8
Sprint, T-Mobile, and Verizon carefully set their iPhone X deals in place before the smartphone went on pre-order on October 27, but not AT&T. Apparently, the carrier has decided against launching an aggressive promotion in support of Apple's iPhone X.
Basically, AT&T is convinced that it can compete with other carriers and win simply based on its product offerings despite the fact that it will not have any promotions on the iPhone X.
It remains to be seen whether or not AT&T's iPhone X strategy will be fruitful or customers will look for alternatives offered by other carriers in the country.