Customized Software Development Business

If you look around for software development companies, You will

see a lot of companies providing services in the areas of BPO, Web

Development, Data Entry, Networking Solutions etc.

The topic which I want to discuss here is that these companies offer

Accounting Software, Payroll Software, Inventory Control, Production

Management, Supply Chain and many more. But the problem is source code,

Generally no one give the source code. I saw a Karachi, Pakistan based company named RSI Business Solutions (http://rsi.bizz.cc) which is providing Software Development Services with Source Code option and other Outsourcing facilities.

Is source code really necessary for a company which is looking for a
Customized Business Software? What do you think?

Also in Pakistan people use the terms Pakistani Style Software, Pakistani

Accounting Software, Pakistani Payroll Software, Pakistani Inventory Software,

Pakistani ERP for Small and Medium Sized Companies (SME) etc., What does it

actually mean?

Never heard the phrases Pakistani Style Software, I'd be interested in knowing what's meant by that too.