Some mobile operators are giving free minutes within their network. Is it really benefit to consumer?

These plans are beneficial for customer if majority of his calling is on the same network. As the cost for same network calls are much lesser (no, its not zero) than calls on another network telecom companies often tend to give certain minutes of calling on their own network free to consumers in certain tariff plans, but the rates for calls to other network are usually higher than normal in these plans. You can easily compare two such plans from different companies by focusing on how many minutes are being offered free, what is charge of same network calling after the free limit, what is the charge of other network calling and how many of your calls are expected to be on other network

There are no costs associated with calls within the same network that's why they offer the service, if you have lots of friends on the same network - it's a benefit

What you don't charge for one thing, you'll charge something else for.

Like on the wireline side of things, talk is literally cheap, with razor thin profits on airtime. The money to be made by phone co's is on the data side, selling internet access, downloadable ringtones, streaming audio and video, massive blocks of txt messages, GPS navigation, etc.

So the wireless co's are more than willing to do unlimited nights and weekends and free in-network calls 24/7 if it means customers start migrating toward their more value-added services. Think of them less as phone companies and more like information providers.

There are no costs associated with calls within the same network that's why they offer the service. this is to make the people attractive on their products

It's just an incentive for you to use more minutes, which in the end benefits them business-wise.

It's only a benefit to you if you do not use more minutes than those you have already paid for (or will pay for) as well as what they give you. Otherwise, if you use more than this, they come out ahead in the end.

Nothing in life is for free

yesssss

it's because of competition

just one more marketing gimmik :P