In my Opinion
Alwar ke pass passengers kam isiliye hain kyunki Rewari ke pass Delhi, Mumbai, Kolkata, Chandigarh, Jaipur, Ahmedabad, NorthEast, Bikaner, Jodhpur, Udaipur, Barmer, Ajmer etc. ke liye better connectivity hain aur isiliye Alwar ke logon ko aur jagah par jaane ke liye dusre stations se board karna padta hain.
Aur...
more... rahi baat unreserved ki toh
Before Covid
Alwar se trains jo Unreserved hain woh kuch is tarah hain
Express + Superfast=57
Passengers + DEMU= 6
Total= 63
Rewari se trains jo unreserved hain woh
Express + Superfast= 84
Passengers + DEMU= 21
Total= 105
Conclusion: Due to odd timings, heavy rush and less frequent trains with unreserved coaches as compared to Rewari, people had to shift from rail to road. That's why unreserved passengers are less in Alwar as compared to Rewari.