its not uncommon.. many serials show that...
Ishqbaaz had first lohri pooja done by newly weds...
Kundali Bhagya had lohri k phere for new couples which are equivalent to shaadi k phere...
in movie Veer-Zaara, they had a ritual that a guy can propose a girl by breaking a stick and if girl wants to accept she throws sesame seeds and popcorn in fire...
and lohri ki aag k phere to hr culture me maane jate h...