I'm not good enough at English to completely understand the difference between the two sentences, but I think it's about politeness. If so, Doomer is quite right. The Russian sentence with 'же' sounds like a gentle reproach with a bit of perplexity. But that's what is usually implicated, the most obvious meaning of this phrase. One can say it sarcastically or in much more other ways. The sentence "Что вовремя не писали, на приёме?" - especially with что like чё - is just rude. So 'же' here is an intensifying particle (усилительная частица) for что (which means why in this case).