2008 Honda Accord Alignment - Drifting to the right

Just bought used 2008 Honda Accord EX L w/ 26800 miles and clean carfax from dealer. Noticed when we finally drove it on freeway that it drifts to the right slightly on most roads. I brought it back to the dealer because they said they would do alignment. They said they DID NOT NEED TO do alignment because they test drove it and found nothing wrong. The service manager also said that this vehicle is made to slightly turn right after 7 seconds. Is this true? Please help. My wife is pissed.

note: tires and rims are 20" which is bigger than factory recommendations. Tire pressure was also checked.