Unless you feel you are being discriminated against on some protected basis--i.e. because of your race, sex, disability, etc.--the law does NOT require that all tenants be treated the same. Your leases, for example, may have different clauses, it would be legal for some leases to have a no pets clause and others to not. Or the landlord may grant permission to some tenants to do something that their leases would otherwise prohibit, but not grant that permission to other tenants. Unfortunately, except as per those few, specially protected categories, the law does not require equal or identical treatment for all tenants, and landlords may, broadly speaking, act more favorably to some than to others.