I doubt the figures for Lahore, as there is tendency among urban Punjabis to claim Urdu as there first language. And secondly, what are the percentages, how much of Lahore is Urdu speaking. I have several relatives in Multan, and Muhajirs occupy distinct neighbourhoods.
As far as I know, Lahore is one of the most homegenous cities in South Asia, so need for Bal Thakray or Shiv Sena like organization. My wife is Lahori Punjabi, of mixed Kashmiri and Arain background. My Susrali tell me even caste wise, its mainly Kashmiri (Butt Mir etc) and Arain (Chaudhary & Mian). Both these castes ape the Muhajir culture, teach there kids Urdu, eat Paan and listen to ghazals. My wife speaks better Urdu then me. I suspect a lot of the Urdu speakers in Lahore belong these communities.
LOL, I can assure you khan sahib, no one in Punjab would like to make a claim and that too false of being an urdu speaker.
As for caste wise its mainly jatts, kashmiris and arians that are dominant and proudly display their casts as surnames. They are also more successful in business, education and politics, hence they appear more prominent than the rest. Lahore has more than a million pushtoon sas well.
Its true that many Lahoris are very fond of eatign paans but no they don't listen to ghazals and they don't see any pride in being called urdu speaking