If you were really a television network executive, you would not hire multiple market research firms to each recruit a different sample of respondents. Instead, you would likely hire only one market research firm. If this is the case, why should you care about the theoretical distribution of mean ratings of multiple samples if you are only going to hire one firm and get one sample and one mean from that sample? To draw conclusions about the population mean using a sample mean, you need to know the theoretical distribution of the possible values the sample mean ratings could have. You should not care about the possible distribution of mean ratings. You should only care about the mean and perhaps the highest and lowest ratings. You need to know the theoretical distribution of possible values of the sample mean ratings to know whether the market research firm recruited the right sample.